Hadoop: «ERROR : JAVA_HOME is not set»

Question

I\'m trying to install Hadoop on Ubuntu 11.10. I set the JAVA_HOME variable in the file conf/hadoop-env.sh to:

# export JAVA_HOME=         


        

Answer 1

I solved this in my env, without modify hadoop-env.sh

You'd be better using /bin/bash as default shell not /bin/sh

Check these before:

1. You have already config java and env (success echo $JAVA_HOME)
2. right config hadoop

echo $SHELL in every node, check if print /bin/bash if not, vi /etc/passwd, add /bin/bash at tail of your username ref

Changing default shell in Linux

https://blog.csdn.net/whitehack/article/details/51705889

Answer 2

You can add in your .bashrc file:

export JAVA_HOME=$(readlink -f /usr/bin/java | sed "s:bin/java::")

and it will dynamically change when you update your packages.

Answer 3

• hadoop ERROR : JAVA_HOME is not set

Above error is because of the space in between two words.

Eg: Java located in C:\Program Files\Java --> Space in between Program and files would cause the above problem. If you remove the space, it would not show any error.

Answer 4

Make sure that you have removed the comment tag and changed your JAVA_HOME in the hadoop-env.sh as well as the appropriate .bashrc and/or .profile:

# export JAVA_HOME=/usr/lib/jvm/java-1.6.0-openjdk

should be

export JAVA_HOME=/usr/lib/jvm/java-1.6.0-openjdk

You can set your JAVA_HOME and PATH for all users (make sure you haven't previously set this to the wrong path) in /etc/profile.

Also, don't forget to activate the new change by logging-out/in or by executing source /etc/profile.

Answer 5

I tried changing /etc/environment:

JAVA_HOME="/usr/lib/jvm/java-11-openjdk-amd64"

on the slave node, it works.

Answer 6

Type echo $JAVA_HOME in your terminal to be sure your JAVA_HOME is set.

You can also type java -version to know what version of java you are actually using.

By the way, reading your description it seems your actually writing

export JAVA_HOME=/usr/lib/jvm/java-1.6.0-openjdk

in the file conf/hadoop-env.sh, you should write it in your terminal or in ~/.bashrc or ~/.profile then type source < path to modified file >.